Aqueous preparations of surfactants and cosmetic preparations may be given a pearlescent, aesthetically pleasing appearance by incorporation of substances which, after cooling, precipitate in the form of fine crystals resembling mother-of-pearl in appearance and which remain dispersed in the preparations. Known pearlescents include, for example, the mono- and diesters of ethylene glycol, propylene glycol and oligomeric alkylene glycols and also monoalkanolamides of C.sub.12-22 fatty acids with C.sub.2 or C.sub.3 alkanolamines.
It is also known that the pearlescents identified above form stable dispersions in water or in aqueous surfactant solutions and that the concentrated pearlescent dispersions obtained in this way may be added without heating the preparations to be pearlized, so that there is no need for the heating and cooling otherwise necessary for incorporation to form the pearlescent crystals.
While known pearlescents perform satisfactorily in providing pearlescent properties to compositions to which they are added, it is oftentimes desirable to further boost/enhance these properties in order to obtain a deeper, richer pearl quality.